Burnishing tool



June 19, 1945. *I A. E. COMISTOCKl BURNISHING TOOL Filed Oct. 5, 1942 IN VE N TOR ghz/IQ 1528. c ,g

Y ATTORNEYS.

Patented June 19, 1945 y UNITED STATES l'nN PATENTMIOFFNICE n'. l nA2.a:7as3s n f l,

n `BURNI'SHING 'rooL Aifrea'E. Comstock, Detroit, Mich.; assigner to TheMurray Corporation ofAmerica, Detroit,

Mich., a corporation of Delaware Application October5, 1942, Serial No;460,883

` n 7 claims. r(Giza-90) This invention relates to burnishing tools, andparticularly to altool for1 burnishing the scratch marks `which may bepresent in a surface of a sheet of material. I

In the copending applications of R. D. I

applicationsemploy a segmental spherical tipv driven in rotation andmoved along the scratch marks to iron the niietal atlthe sides of themark into the` bases of e mark and into abutted relation to close andseal the mark. The Haberstump application includes friction wheels whichprevent any oscillating movement from being transmitted from theburnishing tip to the tool proper and which guides the tool along thescratch mark. A lubricating roller is employed adjacent to the tip forlubricatingthe metal of the scratch mark and also the tip to prevent thewearing of the tip and the over-Working and tearing of the metal. Thetearing of the metal also occurs when too great a pressure is applied tothe tool for forcing the tool into contact with the metal to beburnished.

The present invention pertains to the use of a spring-pressed burnishingtip by which the amount of pressure applied between the` tip and thesurface of the sheet is regulated Stops are provided on the wheelbracket which prevents the spring from becoming solid. A predeterminedspring pressure is always applied between the tip and the metal to beburnished `and theoverworking of the metal through the application oftoo much pressure is thereby overcome. The invention also pertains tothe use of an oil wick directly adjacent to the burnishing tip for con--nished; to mount the stem of a burnishing tip` in a sleeve having a slotin which a pin in the stem projects for securing the stem within thesleeve while permitting limited movement against p a spring provided inthe sleeve; to provide a lubricating wick directly adjacent to theburnishing tip for lubricating the area of engagement i between the tipand neral being burnished.; and

in general, to provide a burnishing tool. which is positive in operationandweconomical of manu-` facture. I M. i

Other objects and features of novelty ofthe invention `will be eitherspecically pointed out or will become 'apparent when referring,` for abetter understanding. ofthe invention, to Vthe following descriptiontaken fin `conjunction with the accompanying` drawing, wherein: .I i

Figure l is a View in elevation of a burnishing tool, illustratingfeatures of` this inventionwith` i Fig. 3 is a broken Iview of structuresimilar to and,

Fig. 4 is an enlarged sectional View 0f the struc-` Fig. 2, taken on theline 2`2 4thereof..`

ture illustrated in The burnishing tool of the Vpresent invention isemployed primarily for burnishing scratch marks which are present on the`surfacel of the Alclad sheets. i 'I'Ihese aresheetsnmade of aluminumalloy having a.` layer .of4 `pure aluminum thereon. The aluminumprevents `deterioration and Oxidation of the core portion and. whenscratches .are made on the face of the sheet the core metal is exposed.Y The tip of thepresent tool is mounted Vinert-center relation to thedriving shank for the purpose `of working the metal ateach side of themark into the base .ofthe mark and into sealed relationwith eachother.

The tool embodies the motor portion I Il, the

driven chuck or collet II in which thetool I2 is secured. A bracket I3is securedto the `housing of the motor portion by a cap I4 and bolts I5.`A wheel supporting bracket is secured by a shaft Il to the bracket I3and is provided with tabs I8 `which abut against the bracket I3 to limitthe `ure 1.

Between the arms 26 of the bracket I9 a tubuwhich it is securedk by anut 3l.

from' being: directlyk applied to the?, tip 36';

y39 urges the stem outwardly of the sleeve. and

provides a predetermined pressure on the.. tip. to

regulate the force of contact with thesurfacefbeing burnished.

When a scratchmark in a: sheet-.41 isy to be burnished, the wheels 24are disposed equi-dis-e tant on'each side of the mark and the motorportion;` Ifilis moved; downwardly to; havefthei tip:

36 contact' theamarlr.y Thefstop` tabs Ij8'I contact the bracketv I3,asfiillustrated'ini Figure 3f, and limit the downward movement of thedriving portion I I." of the tool tof prevent'.1thet pressure Themaximum'. pressure on' the tip. will bef* that exerted by: the spring:39T.` which will? be sufficient tov produce theT bumishing'operationwithout unduly working the-metal being' burnished. The wick 32? will?,be disposed" directly adjacent tothe tip wiien=the1 tip contacts. thesurface,` as'iillustrated in Figure 3*, and will? lubricatet the! metahand tip as the burnishing operation progresses.l

The flow of:v air'througli.I the conductor 42i oiy the motor portion Iof the too'risontrolled'by the pivoted' armst 43" which actuates aplunger v'of/acontrol valve, (notfshown). Aistheeccentric' tip 3'6 israpidly" rotated onthe center line of the scratch mark the wheels '24stabilize the devicefandi guide thex tipV as the device is moved?backward and* f ofrwardly along: they mark; The wheels limit thedownward movement ofthe tip-tof preventthe direct; applicationiofpressure thereto.

What* is claimed is: y

1. burnishing toolf` including a tip havingM a segmental spherical endfportion and a shank portion; the axis off the end portion being oii'setfrom that diA the` shank portion whichl passes through theend portion,`a sleeve supportingsaid shank` portion', andi a spring urging said shankportion outwardly* of" the sleeve, and means for driving said shank inrotation.

2-. 1`n azdevice for'burni'shi-ng the surfacev of'a materialfin'cluding,irr combination, a drivenelement,` aA burnislu'ng' toolsupported bysaid' element; s aid'.' tool embodying; a burnishingf tip-4havinglimited outwardS movement, a spring for urging" saidtipdownwardly; aI bracket, a wheel supporting arm on said bracket, a wheelon said arm, and stop means for limiting the movement of the wheelsupporting arm on said bracket for 3. In a burnishing tool, a drivinglportion, a

portion driven in rotationotherebyl, a burnishing toolsupported by saiddriveni portionvhaving a shank and a burnishng tip axially offset fromthe shank which is of less diameterthan said tip,.a spring-pressed Wheeldisposed adjacent to saidl burnishing tip, and a tubular elementcontaining a lubricant and a wick supported adjacentto said wheel;4

, 4;,111. a` burnishing device, a driving portion, a driven portion, aburnishing tool rotated by said' driven portion, said burnishing toolhaving a burnishing tip, the axis of which is oiiset from the axis ofrotation of said driven portion, a bracket anA arm; pivotedv on; saidbracket-a1 wheel supported onsaid; bracket son as to be; disposedbelow-r the tip of said burnishing to o1,. andr a tubular elementsupported by said arm; containing a; lubricant; and a: wicky alignedvwith said; tip andl disposed adjacent;A thereto'. when the; tip, ismovedidownwardly relative'topzsaid?wheels to be in :contact with-thesurface to be burnished.-

5; Inra burnishingd'evice; a driving portion, adriveni portion; a: toolsupported by said driven portion comprising a: tubular element in whichtheishankof: a burnishing tipzisl secured for limite'd movement when,urged; outwardly of the sleeve. by' a spring,` a bracket supportedonzsaid device; avspring-pressed wheel disposed adjacent tov saidti'p, aspring for: urging saidwheel belowssaidn tip, anda stopelement'forlimiting the upward movement of said Wheel' relative tosaidtip'.A to preventv the application of the applied pressure directlyrtosaid? tip.

6. a burnishing tool', adriven portion, a portion for'driving said-1driven portion in rotation, a spring-pressed" tiprotated" by said drivenportion with theI axis of' the tip in off-center relation tou the axisAoff thedriven portion which latter axis fall'sjwithin the tip; and means`for limiting the downward movement of said tip when'.` contactingthe-surface of a sheet of metal to be burnished;

'7; In an burnishing tool, a driven portion, a portion for driving saiddriven portion in rotation, aspring-pressed tiprotated by-said drivenportion with the aX-is ofthe tip in off-center relation `to theaxisA ofthe driven portion, means forlimiting--the downwardmovement of said tipwhen contacting the surface of a sheet of metal to beburnished, and'awick containing-a lubricant disposed adjacent to said tip whencontacting said'surface.

ALFRED COMSTOCK.

